Friday, August 29, 2008

I took EGirl to the dentist last week right before school started, to get the shining of the pearly-whites out of the way before life got more hectic. My dentist and I chatted once again about the topics that intrigue me: the safety of fluoride (whether in water or toothpaste) and the possibility of a link to bone cancer in boys (see this Eugene Weekly review of the issue from 2005 for a great overview of the controversy); sealants and whether BPA leaching out of them is a health concern; and mercury fillings' wastewater as an environmental hazard. My dentist is pretty comfortable with these topics, well-read, and open to discussion. She didn't come down definitively on any of the issues (hot button topics that need more research in all cases). We both were pretty middle of the road in terms of seeing a true need for cavity prevention (literal British teeth in our family), but she did comment that the ADA conference, which she recently attended, didn't address any of my questions. She suggested I write the ADA to tell them to at least put these issues on the docket for their next round. Even if these topics turn out to be non-issues, you'd think dentists would want to discuss fully how to allay their patients' fears given the level of BPA press alone this year.

I recently took my child to the dentist and had a number of questions for my dental health provider. Apparently, none of my questions were addressed at the last ADA conference (which she'd just attended). I would like to outline my areas of interest in the hope that the ADA will be able to discuss and continue to study these issues within your professional community. I am aware that the ADAs official positions on fluoride and BPA are on the ADA.org website, but in both cases the ADA acknowledges that more research needs to be done to determine if a health concern exists. Please continue to discuss these topics and to inform the public about updated studies of the safety of these chemicals.

1.Fluoride

With regard to fluoridation of water, as the ADA states on its website, there is a controversy regarding a possible link between fluoride supplementation and bone cancer in boys (my dentist mentioned that this was a "hot topic" in Sweden at the moment and that the issue seems to arise cyclically).

While reading up on the issue, I came across the following additional environmental concerns about fluoride: 1)that the type of fluoride used in municipal water treatment may have persistent organic pollutants bound to it (because "most is industrial waste: sodiumfluoride, sodium fluorosilicate and fluorosilicic acid from phosphate fertilizer, glass, steel and aluminum production. Unlike organic fluorine, these compounds come with pollutant hitchhikers that get a free ride into public water supplies." (via ScienceDaily) and 2)even the levels of fluoride considered safe for humans may be affecting marine organisms.

Regarding the possibility of a bone cancer link, the ADA in 2006 put out a press release noting that it "will require scientific confirmation to confirm or refute the findings." I wonder if there's been any more recent research on this topic? What about the other areas of concern ie the ingestion of persistent organic pollutants and the effects of fluoride on marine life?

2.Sealants

Regarding the BPA in sealants, some research seems to indicate that it may be soluble in saliva at high levels during or immediately after application. (In the March 2006 Journal of theAmerican Dental Association, researchers tested 14 volunteers immediately after sealant application and found that patients who received Delton Light Cure (LC) Opaque brand absorbed about 110 micrograms of BPA, 20 times that absorbed by recipients of another brand, Helioseal F (5.5 micrograms). Delton Light Cure (LC) leached amounts similar to those that caused developmental toxicity in rodent studies and, at 42.8 parts per billion (ppb), are higher than thehighest amount found in canned food, 38 ppb.... ") Is there an alternative to BPA-based sealants that is effective and safe? I tend to try to avoid potentially toxic chemicals (like endocrine disruptors) even if the jury's still out because I have young children with developing bodies. If I am getting rid of a baby bottle that may or may not leach minute amounts of BPA, I certainly want to avoid a massive ingestion of BPA during the application of a tooth sealant.

The ADA's public statement on Bisphenol-A concludes that "any concern about potential BPA exposure from dental composites or sealants is unwarranted at this time. When compared with all other sources of BPA, these dental materials pose significantly lower exposure concerns." While it seems that the aforementioned study might contradict that statement, I am no scientist (just a concerned mother). So I am thrilled to read that "the ADA is a professional association of dentists who remain committed to the public’s oral health. As such, we strongly support additional research into human exposure to BPA and any health effects it may cause." Could you update me as to the status of the BPA research the ADA's aware of? Is the ADA continuing with an internal dialogue on this matter?

3. Mercury Pollution

It's my understanding that research has shown mercury amalgalm fillings to be safe for humans -- but it sounds like the wastewater leaving dentists' offices may be polluting our water supply.

"Mercury is a large component of dental fillings, but it is not believed to pose immediate health risks in that form. When exposed to sulfate-reducing bacteria, however, mercury undergoes a chemical change and becomes methylated, making it a potent, ingestible neurotoxin. While the major source of neurotoxic mercury comes from coal-fired electric power plants, researchers at the University of Illinois at Chicago and at Urbana-Champaign say mercury entering drainwater from dental clinics and offices is also a source. "We found the highest levels of methyl mercury ever reported in any environmental water sample," said Karl Rockne, associate professor of environmental engineering at UIC and corresponding author of the study that appeared online March 12 in the journal Environmental Science and Technology." (via EurekaAlert)

What is the ADA's stance on this topic? Is there any safe alternative to mercury-based fillings? How might dentists mitigate the environmental pollution associated with drain water?

Thank you very much. I am not trying to be alarmist about any of these topics, and your website does a good job of addressing the ADA's stance on both fluoride and BPA. I'd just love to see further study and conversation about all of these topics.

Good job Mama Bird - that's one well-crafted letter! Thanks for the detailed research on sealants - I had heard they were a source of BPA but had never read the gory details. Thankfully, my dentist has never pushed the sealants - but my 8 year old just got his first cavity - yikes!

There was an interesting discussion recently on a radical unschooling list about remineralization and nutrition to treat tooth decay. Here's an article from Prevention Magazine: http://mizar5.com/heal.htmI do not trust our dentist, who wants to drill and fill pin-point cavities. Don't trust that the ADA is that concerned about preventing cavities. We'll be shopping for another dentist in AR, but I'm googling more "healing cavities" info.

Really good blog and well crafted letter. My dentist has been very open to discussing all the issues, and even getting MSDSs on products used. My 5 year old has had 2 root canals!!! and on his firt we put a silver cap - made of stainless steel. But it appears that he has an allergy to nickel (when present in his mouth) so now we are researching together options for the permanent (for baby teeth) cover for his other root canal.

This just in from my food-allergy listserve: your child's fluoride treatment may contain nuts!

As one listmember wrote after she called the manufacturer: "According to the rep I spoke with, one of the ingredients was either pine nuts or a close chemical relation to it... She also stated that the dentist would have to call forthe full allergen information..."

Behind the Domestic Curtain

The hormone-ridden water that threatens to turn my baby into a hermaphrodite? Yeah, that could have been one of the driving forces behind my quest for info about simpler, cleaner living on the home front. That and my affliction: careful consideration, aka hair-splitting, about really anything and everything that affects my children. Oh, and lest I lead you astray, I am a serious nester. I love to be in my home, messy little pit though it is, more than almost anyplace else. Why not fine tune every aspect of the nest? With the people I love, in this cozy space, I am surely the luckiest Mama Bird on earth.